The task of determining which pixels are to be illuminated along a line segment (vector) defined by two end points in a raster scanned environment is a fairly common one where computer graphic techniques are used to create an image. In high performance graphic systems that task is performed by dedicated hardware. This is usually a good choice, since the task consists of solving equations belonging to a generally well understood class. Much effort has gone into finding ways to solving these equations in hardware with a minimum of time, so that the pixel determination hardware does not become an obnoxious limitation in restricting the rate at which manipulations to the object can be shown in the display. The present disclosure concerns a way to get the results of such pixel determination in less time than would ordinarily be required. The technique to be disclosed is compatible with the Bresenham algorithm, although use of that algorithm is not a requirement. Also, the technique to be disclosed is not limited to the selection of pixel-position; in a more generalized form it may also be used to interpolate the successive values of any dependent parameter as a function of sequential steps in an independent variable.